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H Ikenaga T Ogihara S Iyori S Kou H Yoshikawa M M Okura 《Postgraduate medical journal》1989,65(768):761-764
A case of a young Japanese woman with long-standing ulcerative colitis complicated by preinfarction angina due to Takayasu's aortitis is presented. Successful emergency aorto-coronary bypass operation was performed. Whether the association of these two diseases can be explained by a common mechanism is discussed. 相似文献
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根据热分析谱图峰顶的数学特征与Coats-Redfern方程,推得在一定实验条件下,在系列相关反应中,若峰顶温度相接近,则各反应的表观活化能E与指前因子A之间存在着有动力学意义的补偿效应,即lnA=aE+b。并经系列含水硫酸盐脱水反应实验验证。 相似文献
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目的:探讨不同供者来源脐血混合移植的可行性和植入特性。方法:分别将两份人HLA半相合混合脐血或单份脐血输入经亚致量照射后的严重联合免疫缺陷(SCID)小鼠,观察两组脐血在SCID小鼠体内的植入状况及多系造血重建特性。结果:混合脐血和单份脐血移植均可在受鼠体内植入,形成供-受混合嵌合体,并能重建多系造血,存活率和植入率无统计学意义(P>0.05)。用多聚酶链反应-序列特异性寡核苷酸(PCR-SSO)探针检测人HLA-DQB1基因发现,HLA半相合混合脐血移植可有1份或2份脐血植入,其中造血祖细胞含量和体外克隆形成能力高者,更易于植入,造血重建特性与单一脐血移植比较无统计学意义。结论:HLA半相合人混合脐血可同时在SCID小鼠体内植入,形成来自供-受三者的多嵌合状态,并能重建造血及免疫功能。 相似文献
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Sinko P. J. Leesman G. D. Waclawski A. P. Yu H. Kou J. H. 《Pharmaceutical research》1996,13(4):570-576
Purpose. To develop, validate and apply a method for analyzing the intestinal perfusion data of highly permeable compounds using the Numerical Aqueous Resistance (NAR) theory and nonlinear regression (NAR-NLR) and to compare the results with the well-established Modified Boundary Layer (MBL) Analysis.
Methods. The NAR-NLR method was validated and the results were compared to the MBL analysis results using previously reported cephradine jejunal perfusion data. Using the Single Pass Intestinal Perfusion (SPIP) method, the concentration dependence of intestinal permeability was investigated for formycin B, proline, and thymidine, three compounds reported to be absorbed by carrier-mediated transport processes. The MBL and NAR-NLR analyses were then applied to the three sets of SPIP data.
Results. The results demonstrate that the intrinsic MBL transport parameters were highly variable and, in one case, the analyses failed to give a statistically significant Michaelis constant. The MBL mean dimensionless wall permeabilities (P*w) were greater than the NAR-NLR P*w and were also highly variable. In all cases, the NAR-NLR variability was significantly lower than the MBL variability. The extreme variability in the MBL-calculated P*w is due to the sensitivity of P*w when the fraction of unabsorbed drug (Cm/Co) is low or, alternatively, when P*w approached the aqueous permeability, P*aq.
Conclusions. The NAR-NLR method facilitates the analysis of intestinal perfusion data for highly permeable compounds such as those absorbed by carrier-mediated processes at concentrations below their Km. The method also allows for the use of a wider range of flow conditions than the MBL analysis resulting in more reliable and less variable estimates of intestinal transport parameters as well as intestinal wall permeabilities. 相似文献
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Abe Y Chinzei T Isoyama T Kobayashi S Ono T Saito I Iwasaki K Ishimaru M Baba A Kouno A Ozeki T Tohyama T Imachi K 《ASAIO journal (American Society for Artificial Internal Organs : 1992)》2003,49(3):325-332
The undulation pump total artificial heart (UPTAH) is a unique, implantable, total artificial heart (TAH) that uses undulation pumps. To achieve long-term survival in animals with physiologic hemodynamic conditions, a control method based on conductance and arterial pressure was applied to UPTAH. With this control method, called 1/R control, survival periods of 50 days (No. 0016, 49.6 kg) and 54 days (No. 0030, 42.5 kg) were obtained in adult female goats. In No. 0016, 1/R control was applied to the left pump, whereas in No. 0030, it was applied to the right pump. Another pump was used for left-right balance control. The control stability was better in No. 0030 than in No. 0016. The sucking effect of the left atrium was remarkable in No. 0016, possibly because of a time delay when left-right balance control was performed with the right pump. In No. 0016, the cause of death was probably a thrombus flown from a panus in the left atrium. It is possible that the left atrial suction effect influenced the thrombus and panus formation in the left atrium. In No. 0030, the cause of death was a small rupture of the membrane in the right pump. The rupture may have been caused by excessive negative pressure inside the pump. This pressure resulted from suction of the right atrium because of an unexpected control excursion, which was probably caused by a software bug. It will be necessary to redesign the undulation pump and improve the software to achieve longer survival periods for animals with physiologic hemodynamic conditions. 相似文献
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目的研究自体骨髓间充质干细胞(MSC)经冠脉内注射治疗急性心肌梗死(AMI)的有效性和可行性。方法球囊阻塞法制成AMI模型。经冠脉注入标记的MSC,4周后核素心肌断层显像检测相对心肌梗死面积、心肌灌注评分和射血分数,经导管检测左室收缩压(LVSP)、左室舒张末压(LVEDP)、压力升高最大速率( dP/dt)和压力下降最大速率(-dP/dt)。免疫荧光法分析MSC的植入和分化。结果与对照组相比,细胞治疗组射血分数显著增加(P<0.05),心肌灌注评分和相对心肌梗死面积显著降低(P<0.01,P<0.05),LVSP、 dP/dt和-dP/dt显著增加(P<0.05,P<0.01,P<0.01),LVEDP显著降低(P<0.05)。标记的MSC在心肌中阳性表达肌凝蛋白重链、连接蛋白43、平滑肌肌动蛋白和Ⅷ因子相关抗原。结论MSC在体内分化为心肌和血管组织,可改善AMI猪的心功能。 相似文献
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目的:研究血管内皮生长因子(VEGF)体外促进小鼠胚胎干细胞系ES-D3向造血分化的能力。方法:先将ES-D3形成拟胚体,将拟胚体细胞转入含不同浓度的VEGF和VEGF+SCF的培养基中。实验分6组,分别为VEGF 5 μg/L组、VEGF 10 μg/L组、VEGF 20 μg/L组、VEGF 5 μg/L+SCF组、VEGF 10 μg/L+SCF组、VEGF 20 μg/L+SCF组,同时设不加因子的自发分化对照组。RT-PCR检测造血转录基因GATA-2和早期造血细胞基因c-kit和β-H1的表达,流式细胞仪检测CD34+细胞,甲基纤维素半固体培养法检测生成造血集落的能力。结果:经过1周的诱导培养,实验组生成的细胞可以表达GATA-2、c-kit和β-H1,CD34+细胞的比例也升高,并可形成造血祖细胞的集落。从诱导生成CD34+细胞的比例和生成的集落数量看,VEGF联合SCF组的诱导效率要高于VEGF单用组和对照组,其中以VEGF 20 μg/L+SCF组和VEGF 10 μg/L+SCF组的诱导效率最高。结论:VEGF能够促进ESC的早期造血分化,尤以与SCF合用时,其诱导效率更高。 相似文献